I have wired up my Raspberry Pi (RPI-0007) to the pins as outlined by http://www.modmypi.com/blog/ds18b20-one-wire-digital-temperature-sensor-and-the-raspberry-pi. However, when I change directory to
/sys/bus/w1/devices nothing is there.
I have added
dtoverlay=w1-gpio,gpiopin=4 to the boot config file (
sudo nano /boot/config.txt) and rebooted but nothing is working. I have checked the wires, loaded the modules and checked the sensor is receiving power (using an LED on the breadboard). Note I have also tested the sensor on an arduino and it works perfectly - so the issue lies with the pi.
The first picture shows the white wire going to the 3v3 pin and the yellow wire going to gpio4
The second picture shows the black wire going from ground to the ground rail on the breadboard, the other end of the white wire going to the positive rail on the bread board and the red wire taking the power to Pin Three on the sensor.
The third picture shows the wiring for the sensor. The red wire carries power to Pin three, the blue wire grounds the sensor and there is a 4.7kohm resistor going from Pin Two to the yellow wire that finishes at GPIO4.
uname -a: Linux raspberry 3.18.7-v7+ #755 SMP PREEMPT Thu Feb 12 17:20:48 GMT 2015 armv71 GNU/Linux